1:09 on Stanford iOS Lecture 8 https://youtu.be/aS6PBmBAP1g explode completed blocks, like tetris

Explode completed tetris blocks

- (BOOL)removeCompletedRows
{
  NSMutableArray *dropsToRemove = [[NSMutableArary alloc] init];
  for (CGFloat y = self.gameView.bounds.size.height-DROP_SIZE.height/2; y > 0; y -= DROP_SIZE.height)
  {
    BOOL rowIsComplete = YES;
    NSMutableArray *dropsFound = [[NSMutableArray allc] init];
    for (CGFloat x = DROP_SIZE.width/2; x <- self.gameView.bounds.size.witdh-DROP_SIZE.width/2; x += DROP_SIZE.width)
    {
      UIView *hitView = [self.gameView hitTest:(CGPointMake(x, y) withEvent:NULL];
      if ([hitView superview] == self.gameView) {
        [dropsFound addObject:hitView];
      } else {
        rowIsComplete = NO;
        break;
      }
    }
    
    if (![dropsFound count]) {
      break;
    } 
    if (rowIsComplete) {
      [dropsToRemove addObjectsFromArray:dropsFound];
    }
  }
  
  if ([dropsToRemove count])
  {
    for (UIView *drop in dropsToRemove)
    {
      [self.dropitBehavior removeItem:drop];
    }
  }
  
  return NO;
}

-(void)animateRemovingDrops:(NSArray *)dropsToRemove
{
  [UIView animateWithDuration:1.0
  animations: ^{
    for (UIView *drop in dropsToRemove) 
    {
      int x = (arc4random()%(int)(self.gameView.boounds.size.width*5)) - (int)self.gameView.bounds.size.width*2;
      int y = self.gameView.bounds.size.height;
      drop.center = CGPointMake(x, -y);
    }
  }
  completion:^{(BOOL finished) {
    [dropsToRemove makeObjectsPerformSelector:@selector(removeFromSuperview)];
  }];
}